Railway traffic controlling apparatus



Jan. 29, 1935. 5 w BAUGHMAN 1,989,444

RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Dec. 25, 1952 H O 0 i: 6 2 X I IS C2 7 g, X 02 T3] 5 2" 7 2 0 9 A B EQJQQQLTZ X 0 4 X I 1 COIZfPOZ/Qd 12 AN manually I C L 1 0f [12 ca X 15 1 9 ea/dawn? X2 F: wz'zl; (Pa/1% 1 15 conditions" 2 R F mam/Q1209.

INVENTOR George ik'Baaglznza'rz [7/8 A TTORNEY Patented Jan. 29, 1933 My" invention relates .:to railway traflic con- -trolling apparatus; and moreispecifically to appar atus for providing ianindication .to a wayside operator that atr'ain has vacated a given. track "section, or .-for clearing out a highway crossing cut section upon the exitof a train, as well as for clea'ring out detector track sections generally;

One-object of my invention is toprovideapparatusofthe above charactenwhich will not me cause improper operation of :cab or wayside signals in a code system of train control and :way-

1 side signaling. Another object is to eliminate the necessityfor control line wires. imaccomplishing--the above result. Other objectsand scription which follows.

I will-describe one :form of;.apparatus embody- -ing"my-invention;sand will then pointout the novel features thereof in claims.

1: 2 The accompanying drawing is a diagrammatic view showing one=form of apparatus embodying. my invention as employed to provide a .trackclean-"indication" at a wayside location. such as:

- an interlocking tower.

passage of a train,- or toprovide a visual or an audiblewayside-indication that a train has cleared a given section, and in general wherever -=control must be exercised. over indicating or demeeting equipment-associated with a given sec *tion, -it is essential' that the-control functionbe; performed in such mannerthat the safety factorof the signaling system will not be impaired there- 573 by. If control line wires are-avail'ablathese can -be used to transmit the indicating or detectingenergy from the-leaving-end of thesec-tion to the. '--=desiredlocation,- as-"soon as the-section becomesunoccupied. 'Where-such line wires are not avail- -able, it becomesnecessary to transmit the clearor "indicating current-over the rails of the 'track-and'thismust be done in suchmanner as "not to causegundesiredoperation of locbmotivecarried cab' signaling equipment should a locomotive-overrun a signal locationandente'rthe :detector section when the next cut section in ad the method used must Vance 'is occupied. Also;

ginotdecrease' the broken down insulated rail joint .larities.

' protection involving staggered track circuitpo- -The system herein disclosed meets the above requirements and -is oigeneral utility. in

-providing detection or indication control incoded etrack circuitsignaling systems.

55 Referring toathe drawing,:the detectortracksecaimpulsessupplied bytra f pra .wililn q me.snuntd, r i-ii thw is s as bverrwmchtramc .nqrm llrmwe gfm left to. right, is supplied-with;- alternating current ;.-.transformer T is a. continuously ope tinggcur rent interrupter or codetransmitter-QTinwhich, 0 :-p DOses, ofillustra ion, i heassuz edst 1contacts l80 and, 50;:become: c1os d=;. t-. he.ra a

.180 X' and; 50, times penminute, respectively.

1 haaux ia sarelay A may. eic ntro edhmh track relay. ;TR of the n ext; .-,Section in advanc b mi d n s-ized wh n=re1ax.:T i advantages will become apparent from thelde- -=to @obtain an indication oi; the, o ccupied or, m-

occupied, .condition of; section..D -,-E. Mfhe t relay A- is 'energizedscontact;;180.; ft ansmitt r CT".- isefiectiveto codethe current. upp iedtdwimii iof transformer-I1 .fromthe s rce'lireq h .rate of;=.-180...in ter.ruptio s; p n minutea ver i o ;.z,c,ontact sroirelayA.

"Where it is desired to restore-highway cross- "ingsignals to the inoperative condition upon the track relay-ER. avi a, ta' liwirid nsl "its a constantlyaen r iz dllocai windin '32; {Be l m-T isssodesigned-thatit will oll wc he ackiculjrent osin z nw meets I ;.;.1.0.-.an d 9..ll .ialt rn.ate y, t ere supvpl-y a direct current-momaisourcefieafijfi t :Q ha1fand then t'qth fith lzhalf of. the. prima y winding of traniormer. Tistozindueaan alternatin potential-across: tthe l secondary winding ,0 his;

transformer; Thei full-wave elific ifier B i Q0 nected across a. portion? of- :the; circuit involving reactor'X andcondenser. C which circuit istuned to LthevlBO :code frequency. sRecflileri Rk suppl-ies unidirectional current to.thelrelayEswhich-theres --for-e remains energized asllong.as;relayzER2is.fol-

lowing track currentgximpulses; ofaiSOx. ic'odeizfre- -quency. whenrela y F isl'energizedgfront contact 12 13: willbeclo'sedg-"an'dilampG 'of signal Siwill 5 Joe lighted iromthe source -X-O, to provide a pro- *ce ed indication. when sectio'n' is occupied, relay TR will be sh tedjand-will-ceaseto dperate,

so that the potential across 'rela-y F collapse,

; and p k colltaci's lz l4 will become cilosed, enercati ll' plfiollowin irafi transformer T that the numerical impedance,

value of Winding 6 will not change very greatly irrespective of whether the circuit of winding 7 is closed or open. That is, the change in phase angle and impedance of winding 6 is such that the magnitude of the track current will remain substantially the same whetherthe circuit for winding 4 of transformer T is being coded over contact 180 of transmitter CT with winding 7 of transformer T open-circuited, or whether winding 4 is being supplied with steady energy over back contact 8 of relay A, and the circuit of winding 7 is being periodically closed through condenser C Sincerelay TR is of the two-element type, it is apparent that it can be operated by changes in phase relation of the currents in the two elements, without necessarily changing the magnitude of either of these currents.

The periodic closing of the circuit of winding 7 by contact of transmitter CT, although not appreciably affecting the magnitude of the track current, will, however, periodically change the phase of the track current with relation to the current fiowingin local winding 3 of relay TR. to

a sufficient degree to cause operation of relay TR in step with the operation of contact 50. That is,

by proper proportioning of the parts, relay TR can be made to pick up when the circuit of winding 7 is open, and to release when this circuit is closed.

Since the code impulse receiving and translating equipment on a locomotive is so designed as to be insensitive to a phase change of the track circuit current, being in the nature of a single phase device, it will be apparent that the above current of periodically varied phase will cause no cab signal response, thereby eliminating the possibility motive which may have entered section D-E dur- I ing occupancy of the next section in'advance.

of a false signal being displayed aboard a loco- The operation of relay TR in following the 50 impulse per minute phase code causes relay K to become energized, so that this relay will close its front contact 16 to energize indicator L, which provides an indication that section D-E has been cleared by the train. Since relayF and the energizing circuit therefor are designed for selective response to track current of code frequency, transmission of the above phase code over the rail circuit will not affect the indication of the wayside signal S which, so far as the apparatus here illustrated is concerned, will give the stop" indication as long as relay A is deenergized.

In practice, the code transmitter CTmay furnish several codes of different periodic frequencies to selectively control multiple aspect cab and wayside signals in accordance with trafiic conditions in advance, the use of but one such signal control frequency being sufficient, however, to illustrate the novel features of my invention. Also, phase codesfof difierent frequencies selected in accordance with traffic conditions can be used to provide any one of several distinct wayside indications to apprise the operator of the location of trains in advance sections, or for any other suitable purpose, without afiecting'cab or wayside signals.

CT may be used to periodically connect a condenser, resistor, or other suitable impedance directly across the current limiting winding 6, or if preferred, a phase shifter of suitable design may be connected into the circuit of winding 4 of transformer T in such manner as to produce the desired track circuit current shift each time that contact 50 is operated.

If the locomotive cab signaling equipment is of such character as to permit some change in the magnitude of the track circuit current between the successive impulses of the phase code without'causing operation of the cab signals, then operation of the relay TR under this condition can be effected by the combination of a change in the magnitude of the current together with a change in phase. The apparatus herein disclosed can also be used to control a railway switch in interlocking territory, insuch manner, for example, as to prevent operation of the switch until a train has cleared the section in which the switch is located.

Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is: i i

1. In combination, a section of railway track, a source of alternating current, a two-element track relay having one element energized from said source and having the other element connected with the rails at ,oneflend of said section, means for supplying current fromsaid source to the rails at the other end of said section, means locatedat said other end of said section and associated with said current supplying means for pcriodically changing the phase of the current supplied to said rails in such manner that the magnitude of said current remains substantially constant, the change in phase being sufiicient to cause said track relay to follow said periodic phase changes, and train detecting apparatus controlled by said track relay.

2. In combination, a section of railway track, a source of alternating current, a two-element track relay having one element energized from said source and having the other element connected with the rails at one end of said section, a circuit for supplying current from said source to the rails at the other end of said section, means located at said other end ofsaid section and associated with said current supplying circuit for periodically changing the phase characteristicof said circuit without substantially altering the magnitude of the current supplied to said rails to cause said track relay to follow said periodic phase changes, and train detecting apparatus controlled by said track relay. I I

3. In combination, a section of railway track, a source of alternating current, a two-element track relay having one element energized from said source and having the other element connected with'the railsat one end of said section,

'a circuit for supplying current from said source to the rails at the other end of said section which circuit includes an impedance having an appreciable phase angle, means for periodically changing the phase angle of said impedance in such manner that the current supplied to said rails will remain substantially constant in magninude but will be periodically changed in phase to cause said track relay to follow said periodic phase changes, and train detecting apparatus controlled by said track relay.

4. In combination, a section of railway track, a source of alternating current, a two-element track relay having one element energized from said source and having the other element connected with the rails at one end of said section, a circuit for supplying current from said source to the rails at the other end of said section which circuit includes a reactor, means for periodically connecting acondenser of such value across said reactor that the current supplied to said rails will remain substantially constant in magnitude but will be periodically changed in phase to a sulficient degree to cause said track relay to follow said periodic phase changes, and train detecting apparatus controlled by said track relay.

5. In a coded alternating current track circuit system of railway signaling wherein traific governing apparatus is controlled in accordance with the frequency of periodic variations in magnitude of the rail current, the method of providing train detection which involves the application of alternating rail current of substantially constant magnitude but periodically shifted phase to the rails at the exit end of the section when the section next in advance becomes occupied to effect operation of train detecting apparatus connected to the rails at the entrance end of the section and responsive to said periodic phase shifts of the rail current, without affecting the condition of said trafiic governing apparatus.

6. In combination, a section of railway track, a source of alternating current, a two-element track relay having one element energized from said source and having the other element connected with the rails at one end of said section, means for at times supplying current periodically interrupted at a given frequency and for at other times supplying current periodically phase-shifted at another frequency from said source to the rails at the other end of said section whereby said track relay will follow said periodic interruptions as well as said periodic phase shifts of said rail current, trafiic controlling apparatus governed by said track relay when said relay is following said periodically interrupted current, and train detecting apparatus governed by said track relay when said relay is following said periodically phase-shifted current.

track, a source of alternating current, a two-element track relay having one element energized from said source and having the other element connected with the rails at one end of said first section, said track relay being arranged to follow periodic variations in magnitude as well as periodic variations in phase of the current in said other element, means effective when the next section in advance becomes unoccupied for supplying current periodically varied in mag- GEORGE w. BAUGHMAN.

7. In combination, a first section of railway 

